A scale model of an engineered log jam. To test how real-life
log jams can help protect riverbanks from erosion, UB researchers
are studying how model log jams like this one affect the movement
of water in a scale model river.

Last November, University at Buffalo master’s student
Ethan Mamer removed 6 tons of sand — by hand — from a
10-meter-long (33-foot-long) artificial river he was using to study
how water cycles through streams.

The purpose: Mamer needed to empty the river to repair leaks in
silicone caulking that were affecting experimental results.

“It took some thought as to how I was going to get all the
sand out and where I would put it,” Mamer said. “We
toyed with the idea of getting a giant moving dolly, a complicated
pulley system and another couple of plans that were all a little
crazy.”

In the end, he settled on simpler tools: shovels, 55-gallon
barrels and a lot of muscle. The job took five days. Several
students in Mamer’s department, geology, took pity on him and
volunteered to help. Then, in January, after plugging the leaks,
the team spent four more days refilling the sand (video here: http://www.youtube.com/watch?v=X2iCAPee5PY).

Mamer ran another series of experiments. They worked. He was
euphoric.

Welcome to the world of river restoration research.

Though scientists in the field spend countless hours studying
real-life streams, scale models made from lumber and PVC pipes also
play an important role in helping investigators understand
rivers.

At UB, scientists are using such devices to test techniques for
strengthening riverbanks, and to simulate groundwater discharge in
streams — a process that plays a role in removing nitrogen
pollution and supporting wildlife.

These model waterways, called flumes, are awesome apparatuses
that feature flowing water and elements customized to meet the
needs of research projects. They require maintenance (as Mamer
discovered), but the science they support is important.

Details on two flumes at UB, both built by the UB College of
Arts and Sciences Instrument Machine Shop:

Groundwater Simulator

A model river, called a flume, in the Natural Sciences Complex at the University at Buffalo. Heat-sensing fiber-optic cables run through the flume, providing UB geology MS student Ethan Mamer (left) and UB geology assistant professor Chris Lowry with temperature measurements that they use to conduct research on groundwater.

Flume Features: This flume pipes water into a thick bed
of sand to simulate how groundwater bubbles up to the surface of
streams. Heat-sensing fiber-optic cables run through the flume,
providing Mamer with temperature measurements that he uses to
determine how groundwater, which is cool, is rising and mixing with
warmer surface water.

The body of the flume is a 5-meter-long rectangular box, but a
divider runs lengthwise down the center, doubling the length of the
artificial river to 10 meters.

Research Purpose: Mamer and Lowry recently completed a
series of experiments using the flume to model how groundwater and
surface water interact. This work enables the scientists to verify
their field results and improve techniques for locating groundwater
hotspots in real rivers — important information for stream
restoration.

“In zones where groundwater is discharging, you have more
invertebrates, which are a food source for fish like trout,”
said Lowry, Mamer’s faculty advisor. In addition, the cycling
of water from the surface of a river into the ground and back can
help remove nitrogen pollution, which enters streams as
agricultural fertilizer runoff.

Stream Restoration Test Bed

A 7-meter long model river at the University at Buffalo. UB geography professor Sean Bennett (top left) and UB graduate students Seyed Mohammad Ghaneeizad (center) and Donghua Cai (right) are using the apparatus to study river restoration techniques. The flume was built by Kevin Cullinan (front) from the UB College of Arts and Sciences Instrument Machine Shop.

Flume Features: This flume is a 7-meter-long,
2-meter-wide scale model of the Big Sioux River in South Dakota.
Using a battery of instruments that slide along movable guiderails,
scientists can measure the volume and speed of water flowing
through the flume, along with the forces that the water exerts on
structures placed inside the flume.

The “river” drains into a large plastic basin, where
it’s then recycled — pumped through white PVC pipes
back to the top of the apparatus. On a recent afternoon, water was
moving through the flume at a rate of 425 gallons per minute.

Research Purpose: Placing formations of engineered log
jams into rivers can protect stream banks from the erosive forces
of flow, and Bennett and his team are studying which formations
work best: “What should they look like, where should they be
placed, and what should be their frequency in space?” he
said.

To test different stabilization structures, the researchers
place models of the structures into the flume and track how their
presence affects turbulent flow, fluid forces and bed
topography.

The team’s findings will help scientists working with the
City of Sioux Falls and the South Dakota Department of Environment
and Natural Resources make decisions on how to stabilize the real
Big Sioux River, Bennett said. Ghaneeizad says one of the most
exciting parts about the flume work is that it will yield
real-world results: “This is a project that will be used
somewhere in the United States. The results will help someone
— it’s not just a library project.”